Have You Ever Seen a 21-mmol/L Serum K+ Concentration?

A blood sample from an 82-year-old man with non-Hodgkin lymphoma was analyzed. His chemistry results are shown in Table 1. The serum hemolysis index was negative. View this table: Table 1. Chemistry results. 1. What can cause spurious gross hyperkalemia? 2. What is the most likely type of preanalytical error involved in …